| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an exhaust gas purification catalyst excellent in the purification capacity for carbon monoxide even under a low temperature condition. <P>SOLUTION: The exhaust gas purifying catalyst includes a base material 54, a lower layer 57 arranged on the base material 54 and an upper layer 58 arranged on the lower layer 57. The upper layer 58 is equipped with a first catalyst and a second catalyst and the lower layer 57 is equipped with the first catalyst. The first catalyst has Al<SB POS="POST">2</SB>O<SB POS="POST">3</SB>as a carrier and has Pt and Pd as noble metals supported on Al<SB POS="POST">2</SB>O<SB POS="POST">3</SB>while the second catalyst typically has a Al<SB POS="POST">2</SB>O<SB POS="POST">3</SB>-ZrO<SB POS="POST">2</SB>-TiO<SB POS="POST">2</SB>composite oxide as a carrier and has Pd as the noble metal supported on the Al<SB POS="POST">2</SB>O<SB POS="POST">3</SB>-ZrO<SB POS="POST">2</SB>-TiO<SB POS="POST">2</SB>composite oxide. Further, the upper layer 58 has a hydrocarbon adsorbent 68. This exhaust gas purification catalyst is suppressed from the HC poisoning and sulfur poisoning of the catalyst and enhanced in the purification capacity of carbon monoxide. <P>COPYRIGHT: (C)2013,JPO&INPIT |
